This invention relates generally to carriers for semiconductive wafers and, more particularly, to such carriers having provision for impeding spillage of semiconductive wafers therefrom during manual handling of the carriers.
Carriers for holding twelve, twenty-four or more spaced semiconductive wafers each are employed in many types of semiconductive wafer processing systems to facilitate batch processing and to minimize damage of the wafers due to improper handling. Such carriers are employed, for example, as input magazines for sequentially supplying semiconductive wafers to automatic wafer handling and processing systems, or as output magazines for sequentially receiving processed semiconductive wafers from such systems, or as intermediate (throughput) devices for holding semiconductive wafers that may require sampling, testing, or some other special handling at some point during processing by such systems. In nearly all of these cases the carriers must, at some point, be manually transported to or from such systems with the attendant risk that in so doing the semiconductive wafers may slip from the carriers and thereby be damaged or broken. This risk is particularly great in the case of carriers of the type permitting unobstructed passage of semiconductive wafers therethrough. If such carriers are tilted slightly forward or backward while they are being manually transported, any semiconductive wafers contained therein will slide out. Although this risk is much less critical in the case of carriers of the type permitting passage of semiconductive wafers into or out of the carriers from only one end of the carrier, care must still be exercised while such a carrier is being manually transported to avoid tilting it downward in the direction of its open end.
Past efforts to eliminate the risk of spilling semiconductive wafers from carriers while they are being manually transported have resulted in elaborate switching mechanisms for locking the semiconductive wafers in place in the carriers during manual transport thereof. However, the person transporting a carrier with such a switching mechanism had to remember to actuate the switching mechanism before picking up the carrier or run the risk of spilling the semiconductive wafers contained therein, in which event the risk was, in fact, not reduced at all. Moreover, when placing the carrier in a wafer handling and processing system the person transporting the carrier also had to remember to deactuate (or release) the switching mechanism in order to release the semiconductive wafers to the handling and processing system. In addition to these drawbacks, such switching mechanisms are generally complex and add significantly to the cost of the carrier.